Nut-lock.



E. P. WORTH.

NUT LOCK.

APPLICATION TILED 11011.1, 1911.

1,059,420.! Patented Apr. 22, 191 s.

Fit leases; Ira/641 131,

"17/ W 1mm P W wh UNITED; STATES PATENT OFFICE.

ELVIN P. WORTH, OFBOSTON, MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGNMENTS,

TO STEEL SPECIALTIES COMPANY, OF BOSTON, MASSACHUSETTS, A CORPORATION OFMASSACHUSETTS NUT-LOCK.

Specification of Letters Patent.

Application filed; November 1, 1911.

Patented Apr. 22, 1913.

Serial No. 657,913.

have invented certain new and useful Improvements in Nut-Locks, of whichthe following is a specification.

The object of'this invention is the construction of an improved nutlocking device which may be applied to the bolt after the nut has beenscrewed down thereon, and which can be made by a blow or two so to gripthe bolt as to render the nut incapable of becoming accidentally 'loosethereon.f

In the drawings forming part of this specification, Figure 1 1s a sideview of a bolt and nut, showing the nut lockin section thereon. Fig. 2is a side view of said parts, showing the nut look about to be fixed inposition. Fig. 3 is a plan view of the nut lock alone. Fig. 4 is a sidesectional elevation of the nut lock alone. Fi 5 is a side sectional viewof the same, but in the reversedposition which it will assume when ithas beenpressed slightly past a flat con- .formation, but is notrestrained by the influence of the nut and bolt.

This invention is based upon the known fact that when a rounded orconical metallic plate is forced to a flattened position, it will eithersnap back to its former convexity, or to a similar convexity in areversed direction. In 'the utilization of this characteristic, a washer1, illustrated in Fig. 3, is formed with a plurality of centrallyextended fingers 2, theextremities of which are shortened suflicientlyto form a hole of materially less diameter than that of the bolt forwhich the nut lock is designed. Between.

these fingers are radial slots 4 the outer ends of whichare preferablyrounded. It is also necessary, for the increasedresilience of thefingers, to have. their radial length mate-' rially greater than theirwidth. After this washer has been thus fashioned, or prefer- .ably atthe same time and by thesame blow as that which punches it out, it isgiven a cup-shape and made to conform to approximately a frustum of acone, as shown in Figs. 2 and 4. v This formation so separates thefinger ends from each other that the nut lock can be easily slipped downover the bolt for which it. is designed, with its concave surfaceupward, as in Fig. 2. A tubular tool 5 is now applied to the outerportion of Inasmuch as the sheet metal composingthe nut lock is thinnerthan the pitch of the threads on the bolt, and the ends of the fingers 2have a slight play between the said.

threads, and since the pressure of the tool 5 will not permit theperipheral section of the nut lockto rise, the teeth and the innerperiphery of the same are the only parts H which can move, and these canonly move.

upward slightly. But this movement is enough to insure against thepossibility of the outer peripherys snapping upward, and to cause sostrong an opposing pressure of the nut lock between the upper surface ofthe nut and the under surfaces of the teethor threads of the bolt, as tosecurely lock the nut against accidental turning. The said innerperiphery of the nut lock is indicated by the dotted circle A in Fig. 3.

Ordinarily,'the upper surface of the nuts is more orless rounded, asshown in Figs. 1 and 2, so thatit aids in the reversing of the nut lock;but even without this, the latter readily assumes the reverse position,as mdicated in. Fig. 1, because of the slightly steeper angle iven tothe fingers than to the annular art T of the nut lock. As represented inFigs. 2 and 4, the said part 7 is preferably. given an angle of thirtydegrees with respect to the plane of the base, andthe fingers are givenan angle of about fortyfive degrees relative to the same. This permitssaid annular part to assume the desired reverse position with scarcelyany elevation of the ends of the fingers, asrepresented in Fig. 1, andthereby maintains the'nut lock securely in such position. It is evident,therefore, that the nutlock possesses two means for check the rotationof the nut, one

consisting of the centripetal rip of the finger-ends against the boltetween its threads, and the other consisting of the torsional strain ofthe annulus 7 causing its outer periphery to be strongly pressed down-Ward upon thesurface of the nut. The latter pressure engenders frictionwith such surface adapted to keep the nut from-begim ning to unscrew,and so insures against the slightest unloosening of the nut. At the sametime, the insertion of a sharp chiselv edge beneath the outer edge ofthe nut lock is capable of springing the same back, toward its originalposition, far enough 'to permit its withdrawal from the bolt.

This nut lock is consequently very inexpensive to manufacture, easy toapply and easy to remove, While at the same time it is certain andefiicient in its locking function.

ing a plurality of centrally projecting fingers, the annulus and fingersbein conical 1n general contour, and composed of resilient sheet metal,and'the fingers being made narrow radially in order torender themresiliently flexible relative to the annulus.

3. A nut lock comprising an annulus formed. with centrally projectingfingers, the inner ends ofsaid fingers being curved concentric with theannulus, and made substantially equal in width to the space separatingtwo adjacent fingers whereby. they are resilient relative to theannulus, said annulus and fingers beingconical.

4. A nut lock comprising an annulus formed with centrally projectingfingers, said fingers and annulus being conical, the fingers being moresharply conical than the annulus. i

5. A nut lock comprising a washer formed.

with centrallyprojecting,fingers the inner ends of which compose a holeof slightly greater diameter thanthe bolt for vwhich the same isdesigned, said washer being made conical with an angleyof approximatelythirty degrees with respect to the base thereof, and said fingers beingmade conical withan angle of approximately forty-five degrees withrespect to such base.

In testimony. that I claim the foregoing 30th-day of October, 1911.ELVIN P.'WORTH.

Witnesses: Y.

A. B. UPHAM, ALEX. L.'\PECKHAM.'

invention, I have hereunto set my hand this

